066 is the most comfortable, 168 is the heaviest. Patlien really liked the 177 but it has the most aggressive geometry. I'd personally go for the 066; I almost did but went in another direction.

Of course it's possible if the groupset itself is not damaged. With rare high end exceptions where mechanical groupsets can't be installed on some frames, it should be just a straight swap with the exception of new brake hoses and fittings. A few other compatibilities to look out for would be clearance for tire, chainrings, disc rotors but everything is probably fine
By the way the UCI certification is completely worthless and nothing but marketing if you don't race in UCI events. Not indicative of quality in any way